1. Field of the Invention
The present invention relates to a system for recording information about the process history of each system and implementing the reference of a transaction state in a system and between systems, and the collection of charging information and communications logs, etc., based on recorded information in a data processing system composed of a plurality of systems like an electronic data interchange (EDI) system.
2. Description of the Related Art
Recently an electronic data interchange system for exchanging data for business transactions between the systems of different companies has been spread. In such a system, data, such as order slips, order acceptance slips, etc., are transmitted/received between the computers of the different companies via a communications network. In a conventional electronic data interchange system, a method for integrating the history information of a process into a data format in order to transfer a process history between processes or systems, is adopted. According to this method, when each of a plurality of sequential processes is completed, it records a new history in the formats of both input data and output data. In this way, each process history can be transferred to a subsequent process and a process for tracking a history, etc., becomes available.
In a specific communications protocol, etc., history information is managed separately from actual data by integrating the history information into a protocol message. According to this method, a process history can be recorded and transferred to a subsequent process without affecting the format of data.
However, of the conventional process history recording methods described above, a method for integrating history information into a format has the following problems.    (1) Since history information must be stored in data, a format to be used is restricted and a standard format stipulated for each industry cannot be used.    (2) Since history information must be stored in data, a process history stored in data to be tracked must be confirmed when a process history is tracked. In this case, if data distributed among a plurality of systems are tracked, each system must be accessed and a process history stored in data must be confirmed. Therefore, a communications process becomes complex and it cannot necessarily be said to be a general method.    (3) Since history information must be stored in data, this method cannot be applied to a process without data.
The method for integrating history information into a protocol message has the problem that the method cannot be applied to a communication protocol into which history information cannot be integrated.